Flexible terminal strip



Dec. 11, 1956 R. R. SEGER 2,774,053

FLEXIBLE TERMINAL STRIP Filed Jan. 14, 1954 INVENTOR. E055 E. 55655 BYQ EQAW 40w ND United States Patent FLEXIBLE TERMHWAL STRIP Ross R. Sager, Dayton, Ohio, assignor to the United States of America as represented by the Secretary of the Air Force Appiication January 14 1954, Serial No. 404,151

1 Claim. (Cl. 339-198) (Granted under Title 35, U. S. Code (1952), sec. 266) The invention described herein may be manufactured and used by or for the Government for governmental purposes without payment to me of any royalty thereon.

This invention relates to a new and improved flexible terminal strip. The subject invention was developed to meet a need long apparent in the art for a terminal strip adaptable for use with irregular shaped mounting structures and for use where the terminal strip is subject to direct or indirect stress applications. This need has been most apparent in testing apparatus where a terminal strip utilized as a connector device must be removably mounted on the curved or irregular surface of a rapidly rotating element. The centrifugal force due to the rotation caused the terminal strip to slide outwardly on the rotating element against the resistance of the securing means. This disturbed or broke the terminal contacts. The present invention is intended to eliminate these difliculties.

The improved terminal strip presented by the subject invention comprises a block of resilient nonhydroscopic material having a high coeflicient of friction. A plurality of U-shaped electric terminals are imbedded therein and are positioned transversely to the axis of the block and are spaced longitudinally thereof. Because of the resilient base and particular arrangement of the terminals there is efiected a plurality of parallel terminals with a resilient joint between each pair so as to permit relative displacement of the terminals in the strip. The strip may accordingly be wrapped about or clamped to an irregular surface.

An object of the invention is to provide a new and improved terminal strip.

Another object of the invention is to provide an improved fiexible terminal strip having the terminals arranged therein in parallel jointed relation.

A further object of the invention is to provide an improved terminal strip adaptable to irregular shaped surfaces of varying contour.

An additional object of the invention is to provide an improved terminal strip which will conform to an irregular rapidly rotating surface to which it is applied and be highly resistant to movement caused by the centrifugal force.

Other objects and advantages of the invention will become readily apparent from the following description taken in conjunction with the accompanying drawings wherein:

Fig. 1 is a perspective view of the improved terminal strip.

Fig. 2 is a detail view of one of the terminals.

Fig. 3 of the drawings shows the improved terminal strip as employed in application to testing of a propeller.

The improved terminal strip as shown in the drawings comprises a base or support member 1 of molded resilient rubber substantially rectangular in shape. The support member has a single continuous base surface and an upper portion. The base surface is adapted to completely coincide with and frictionally grip a work surface of irregular contour in a rotating device. The upper portion of the support has a substantial groove 2 centrally and longiice tndinally thereof forming two projecting ribs 3 at the top sides thereof. The cross-section of each rib is triangular in shape and the apex of each coincides with a respective top side of the base member. The side surfaces 4 and the end surfaces 5 of the support member are bevelled outwardly and intersect the base surface to provide increased frictional area for holding the support in place against the centrifugal force.

Molded in the base member transversely thereof in parallel fashion spaced longitudinally thereof are U-shaped terminal bars 6 of brass or a material of similar conductive properties. The legs 7 of each of the U-shaped members extend through the upper surfaces of the respective ribs at the top sides of the base member at the apex portions of the ribs in transverse alignment. The upper end of each leg of each U-shaped member has a V-shaped notch 8 therein. The resulting configuration of the terminal strip with the cross bars of the respective U-shaped members embedded in parallel spaced relation therein provides a flexible joining of the terminals so that they may be relatively displaced to conform to the surface to which they are to be applied in a manner which is readily apparent. The V shaped notches 8 in the terminal bar legs provide an eflicient means for securing lines thereto. The central groove 2 facilitates the application of a clamp C to the assembly intermediate the aligned legs of the U-shaped terminal members.

An example of an application of the improved terminal strip wherein its advantages are readily apparent is in the testing of propellers. As shown in Fig. 3 of the drawings, strain gauges in testing are applied centrally of the blade members B. Connector elements are necessary for application to the blade members intermediate the strain gauges and the slip rings of the propeller blades through which a circuit is completed to an appropriate power source and recording apparatus. The prior art terminal strips are inadequate for such an application being difiicult to hold in place so as to withstand the forces applied in testing and moreover they create a general problem due to water vapor forming in damp weather causing high resistance shorts and making the measuring system inoperative.

The subject invention was developed to provide a solution for such problems; to prevent the breaking of connections due to applied forces. As shown in the drawings the base member is applied to the surface of a blade member, wrapped about the blade member and a clamping band C is applied in the groove 2 about the base member. The clamp in this instance is of the hose type. The connecting wires from the strain gauges are inserted in the notches in the respective leg members to the gauge side of the groove and the appropriate connectors from the slip rings are inserted in the notches of the respective legs to the other side of the groove and soldered. The extended undersurface of the base member offers a substantial resistance to stress placed thereon in testing by its frictional engagement with the blade. The provision for clamping further insures the additional stabilization of the terminal U-shaped members initially stabilized by being molded within the base member. Also the use of notches for engagement with the connecting wires provides an easy sure connecting mean which facilitates the firm soldering of the connecting wires to the terminal members. The advantages over the prior art accordingly are readily apparent.

While a single practical embodiment and application of the invention has been shown herein, many other variations and applications thereof will be readily apparent to those versed in the art and such is considered to be within the scope of the invention.

What is claimed is:

A terminal strip adapted to adhere to devices having 13 an irregular contour and which are subject to strong centrifugal'forces comprising a substantially rectangularflexible nonconductive support member, a plurality of elongated conductive terminal members positioned transversely of the longitudinalaxisof the support member, and arranged in parallel longitudinally spaced relation, said support member comprising a single continuous base surface and an upper portion, said base surface adapted to completely coincide with, and frictionally grip, a Work surface of irregular contour on a rotating device, said upper portion having an elongated recessed upper surface centrally positioned between the sides of the support, said recessed upper surface extending parallel to the lon- 4-. gitudi'nal axis of the support member and adapted to receive a clamping strap, said support member having bevelled outwardly extending side surfaces intersecting the base surface to provide increased irictional area for holding the support in position against the strong centrifugal forces.

References Cited in the file of this patent UNITED STATES PATENTS ni'linwood mnamuu Jan. 15,1946 2,396,725 Thomas Mar. 19, 1946 2,509,701 Smith May 30, 1950 

